Thrombosis is a disease caused by blood in a blood vessel forming a clot by some reason to be a thrombus and the thrombus blocking the blood vessel and interrupting the blood stream. In sites downstream of the blocking, infarction and ischemia develop, are called cardiac infarction or cerebral infarction according to the site, and have the risk of becoming a life-threatening situation.
For example, cardiac infarction indicates conditions that the coronary artery is stenosed by thrombi, the blood flow decreases, and that the cardiac muscle becomes necrotic. In the treatment for cardiac infarction, since killing of the cardiac muscle proceeds as the ischemia time increases, and the prognosis becomes poorer as the extent of infarction increases, it is necessary to re-open (re-perfuse) the blood stream promptly.
As such a re-perfuse treatment, as well as the thrombus dissolving treatment for injecting a drug to dissolve the thrombus, there are catheter treatments (PTCA, PCI) for directly expanding the coronary artery to increase the blood flow. In recent years, with the progression of endovascular treatment techniques, methods have relatively been made ease for surgically securing the blood stream and/or removing the thrombus. More specifically, there are the blood vessel expanding treatment for expanding a stenosed lesion area by a balloon catheter, stent placement for covering a balloon with a mesh-shaped tube called the stent, inflating the balloon to fix the stent to the blood vessel, removing only the balloon to place the stent, and supporting the wall of the blood vessel from the inside, and the like.
Further, previously, such an apparatus is developed that a wire is directly passed into a stenosed site of the blood vessel, and that a basket, filter or the like provided in the wire traps an embolus (for example, see PTL 1).